Large anomalous Hall and planar Hall effect in magnetic Weyl semimetal Co₃Sn₂S₂

Weyl fermions are chiral massless fermions manifested in crystalline solids by spin split conduction and valence bands crossing at discrete points. Time-reversal-symmetry-broken Weyl semimetals (WSMs) have attracted particular attention because of their interesting interplay between intrinsic magnetism and topologically nontrivial electrons. In this work, we perform detailed transport studies on a magnetic Weyl semimetal, Co₃Sn₂S₂. Nanoplates as thin as 180 nm were grown via chemical vapor transfer methods. Through magneto-transport measurements, we report a large intrinsic anomalous Hall conductivity generated by a large Berry curvature from the Weyl nodes. The anomalous Hall conductivity is robust against both increased temperature and charge conductivity, reaching ~1420 ohm^-1 cm^-1. In addition, we discuss the observation of a large planar Hall effect (PHE) in Co₃Sn₂S_2. We carefully examined all possible origins of the PHE including ferromagnetism, orbital magnetoresistance and the chiral anomaly. Our analysis reveals that even though negative magnetoresistance (NMR) was not seen, the observed PHE is chiral anomaly dominated. Our results show how multiple PHE contributions can be disentangled in a magnetic WSM system and suggest that PHE is a sensitive probe of Weyl transport.